Flexibility and dexterity in industrial robots:
Demonstrators of new frontiers in industrial
applications
12th March 2015, Vienna, Austria
Compliance robot control for enhanced
industrial robots dexterity and flexibility
D. Surdilovic, Fraunhofer – IPK Berlin
Laboratory for RobotSupportedCooperativeWork
ERF2015 WORKSHOP
Objectives – Nowadays, Future Industrial Robots
Dextereous Manipulation and Flexibile Automation for Manufacturing
Applications
Ambituous, nevertheless logical demands:
Dextereous Manipulation : Area of robotics in whichmultiple manipulators or fingers cooperate to grasp andmanipulate objects;
Flexible Automation : Ability for a robot or system to be quickly and easily re-tasked to change product design for both low and high mix manufacturing (capacity-volume and product variants flexibility)
Robots are currently incapable of competing with human toperform dexterous tasks (contact tasks) in a flexible manner!
Role of compliance (dexterity ↔ flexibility)?
Active compliance control – a 30 years old idea (Mason
1985), still not alive in industrial (conventional) robotics
INTERACTING WITH A GODZILLA
WHICH SENSE IS CRUCIAL FOR CONTACT?
Pioneering work in force and compliance control (since 1987)
Challenges: sampling time, quantization, time lags….
LABORATORY FOR RSCW AT IPK
Actual HRI summary: Everybody moves and guides a robot.
Research on Active Compliance Control (30 years after) :Position based impedance and force control
Target Impedance/Force Position based impedance/force control C-frame
Robust control design
Matlab Toolbox
CartPose cl = hl.getPose();
lArm. setComplianceGains(ENGAGE_CONFIG);
lArm.setComplianceFrame(CartPose())
lArm << MoveLin(cl); CURL++ (ROS)
Open-Control (C5Gopen,
KUKA RSI , ORiN etc.)
Planing and programming
For Compliance Control Testing (including process forces
– modelling/experiments)
AUGMENTED REALITY
CLASSICAL TASKS: GRASPING AND INSERTING
Combined Force/Impedance Control
CRITICAL EDGE FOLLOWING
Things that should never be done!
Improperly designed
controller may be
destabilized by human
Maximum target
bandwidth < one half of
the position control
bandwith
DEXTEREOUS CONTACT TASK – N40 COCKPIT SET
• Several latching mechanisms
• Complex hand motion
• Compliance, motion and
force control - key strategy
• Variation of task execution
• Difficult (impossible)
conventional robot
programming and execution
• Limitations of industrial add-on
tools (e.g. active and passive
compliant devices)
LIFE CYCLE TESTING
CONSIDERABLY SLOWER ROBOT
EXECUTION (SAME FORCE LEVEL)
• Considerable amount of damping
needed to stabilize the interaction
• Relatively slow motion to keep
smaller interaction forces and torques
• Human task: Variable impedance,
rapid change of strategies
• Robotic execution considerably
slower (30 s cycle) vs. human
operation (app. 5 s)
• Development of human-like
strategy
• Action termination based on
interaction force/torque monitoring
Human-task
Improved robotic testing
Dexterous Advanced Robot
Programming
Planning and Programming – main
bottleneck for wider applications of
dual-arm robots in industry
Bi-Manual human operations –
Central interference hypothesis -
content-dependence (Hazeltine 2006) -
Bottlneck is in the planning of the
movement (motor preparation)
Mimic human motion
Simple planning and
programming of human-like
bimanual motion („Callosum“ –
control)
-Symetric/asymetric,
congruent/non-congruent
motions
-Arms collision monitoring and
avoidance
EFFICIENT DUAL-ARM INSERTION (INTERACTION BETWEEN TWO COMPLIANT ARMS)
BI-INSERT(SUBJECT& HL, SUBJECT& HR, DOUBLE SPD=INSERT)CURL++ (ROS PACKAGE)
biInsert is resolved to:
CartPose cl = hl.getPose();
lArm. setComplianceGains(ENGAGE_CONFIG);
lArm.setComplianceFrame(CartPose())
lArm << MoveLin(cl);
CartPose cr = hr.getPose();
lArm. setComplianceGains(ENGAGE_CONFIG);
rArm.setComplianceFrame(CartPose())
rArm << MoveLin(cr);
CartPose cl = hl.getPose();
lArm. setComplianceGains(INSERT_CONFIG);
lArm.setComplianceFrame(CartPose() +Vector3(0,0,-d/2)))
lArm << MoveLin(cl);
CartPose cr = hr.getPose();
lArm. setComplianceGains(INSERT_CONFIG);
rArm.setComplianceFrame(CartPose()+Vector3(0,0,-d/2))
rArm << MoveLin(cr);
lArm.execute();
rArm.execute();
Engage
Insert
FLEXIBLE AUTOMATION + DEXTEREOUS ARMS MANIPULATION – GEAR MESHING
INSTEAD OF CONCLUSION : COMPLIANCE ROBOT ARMS CONTROL -KEY TECHNOLOGY TOWARDS ENHANCED DEXTERITY AND FLEXIBILITY
